A Google Cache Checker tool works by submitting the URL of the webpage or website you want to check to Google and then returning the result of whether or not the page is currently cached by Google. Some tools may also display additional information, such as the date and time of the last cache update.
These tools can be useful for webmasters and SEO professionals who want to check if a website or specific pages are being indexed by Google, or for individuals who want to verify if a website is legitimate and not a phishing or scam website.